The 6-year-old girl was striking, so beautiful that one of the South Sudanese government soldiers who attacked her village near Bentiu in Unity State singled her out.

He would abduct her, the way so many other Sudanese Peoples Liberation Army soldiers were grabbing girls as sex slaves, locking them up and raping them night after night.

The ethnic fighting that had raged across South Sudan for months unleashed unrestrained barbarity, particularly in Unity state. The atmosphere was to grab whatever you could, do whatever you liked. Government soldiers and allied militias were told they could rape and loot, instead of being paid, according to a report by the office of the United Nations Human Rights Commissioner released Friday.

Old men and women were locked in huts and burned alive. Men and boys were shot or crammed into locked containers and left to die in broiling heat. Thousands of women, and girls as young as 9, were gang raped and often killed.

As government soldiers reached a village in Koch County, Unity State, in November, the mother of the 6-year-old girl left her daughter with neighbors while she hurried to get water to carry with her so that the family could flee for a displaced persons camp at a U.N. base in Bentiu.

While the mother was away, the soldier spotted her daughter, according to the report, and decided to steal her. But other soldiers told him she was too young to rape. A violent quarrel ensued and the soldiers started shooting, witnesses later told the mother.

In the same village the previous month, government soldiers killed another woman’s husband in front of her and tied her to a tree. She had to watch as at least 10 soldiers gang-raped her 15-year-old daughter. Another woman in Koch saw her 11-year-old daughter and a 9-year-old friend raped by three government soldiers in May.

Although both sides were responsible for abuses, the U.N. report found South Sudanese government soldiers and allied militias committed most of the atrocities, particularly in 2015, when it was on the offensive, driving opposition forces from their strongholds and punishing civilians of the same ethnic group.

The U.N. recorded 1,300 rapes in Unity State between April and September last year. At least 50,000 people have been killed in a civil war that broke out in the capital, Juba, in December 2013, and swiftly spread as the army and government split along ethnic lines.

It took almost two years to patch together a peace deal, signed in August, but fighting continued for months and deadline after deadline to set up a transitional government has been missed.

According to the U.N. report, youth militias worked with South Sudanese soldiers carrying out attacks that targeted civilians “under an agreement of ‘do what you can and take what you can.’ Most of the youth therefore also raided cattle, stole personal property, raped and abducted women and girls as a form of payment.”

Rape and killings were so brutal and systematic that these seemed to be part of a broader strategy to terrorize civilians from ethnic groups seen as associated with the opposition, according to the report. Women who looked their rapists in the eye, who tried to resist, or who showed their exhaustion and pain after being gang-raped at length were often killed.

“Almost all the people interviewed by the [U.N.] assessment team recounted a relative or friend who was deliberately targeted and killed in an attack,” the report said.

Women often fell victim to attacks as they ventured out to find firewood or food, or as they fled villages because of the approach of government soldiers and allied militias.

Those trying to protect children were often vulnerable. One woman with four children, ranging in age from 2 to 7, couldn’t keep up with others fleeing their village, trying to get to the safety of a camp at a U.N. base at Bentiu.

On the way, she was stopped on the road by government soldiers and armed men, who interrogated her on where she had come from, and accused her of lying. They stripped her and five soldiers gang-raped her in front of her children. Then two more soldiers dragged her into nearby bushes to rape her again. After they had finished the assault, she returned for her children. But the four children had disappeared and were still missing when the U.N. report was written.

Some women stayed behind in their villages vainly trying to protect elderly parents. One woman told how her husband was killed and her father was locked into a storeroom with the family goats and burned alive. She listened to his screams in anguish but could do nothing to help him.

“However, the quantity of rapes and gang-rapes described in the report must only be a snapshot of the real total. This is one of the most horrendous human rights situations in the world, with massive use of rape as an instrument of terror and weapon of war,” he said.

Amnesty International detailed killings in Leer in October, when government soldiers rounded up dozens of cattle herders, mainly men, but some boys, and locked them in a container with no windows or air vents on the grounds of the Catholic Church, which was being used as a military base. The incident was also recorded in the U.N. report.

They were imprisoned in the broiling heat for days, as relatives pleaded for their released.

“Amnesty International has gathered evidence indicating that government forces, including the area commander at the time, stationed immediately outside the container, were aware of the detainees’ extreme distress and decided to keep them locked inside the container even after some individuals had died,” the Amnesty International report said. Witnesses described the prisoners shouting and crying that night inside the container. But then the voices stopped.

Within two days, almost all the men and boys were dead. At least 62 perished, according to witnesses interviewed by Amnesty International.